That is the Jack Howard Hunter. Jack made a 66" bow. His customers loved it, but some asked him to come out withj a 62" model. He did not want to retool and start from scratch for a 62" model. So he bought about 50 (I think that's what he told me" unfinished Howatt Hunters and finished them with his logo and his special finish. Hard as glass. He marketed them as the Jack Howard hunter.
Now the Howatt Hunter is a good bow in its on right, but it is not Jack's limb design with spined matche glass and core laminations, Jack's signature feature.
As far as rarety goes, it is rather rare since he only made about 50 of them. So that makes it somewhat collectible. I don't know what you have in it, but it is worth haveing in a collection, in my opinion. I have one in a right hand version. Mine has a diamond wood riser and I have a Howatt with the same riser. They look identical.
It is not a jet. It is not a Jack Howard desighn. But it is what it is, and worth having.
Good find.